1. Field of the Invention
The invention relates to the field of radiofrequency identification (RF/ID) tags, and in particular, it relates to methods and apparatus for identification of individual RF/ID tags when multiple tags are present.
2. Description of the Prior Art
RF/ID tags may conflict with one another when responding to a single RF/ID reader since the tags are transmitting on the same frequency within the same time slot. A single request to read multiple tags in a field of interrogation can be expected to generate multiple responses which the reader will be unable to separate or differentiate. Therefore, systems in which individual tags use common time frames and frequencies prohibit the use of more than two such tags in an interrogation zone at the same time. What is needed is a method and apparatus by which this limitation can be overcome.